The present invention relates to an insulating terminal cover, and particularly to an improvement of an injector insulating cover for an injector which ejects fuel into an engine. Such an insulating cover is fitted onto a head portion of the injector, covers and insulates a wire connecting portion in a head portion of the injector, and holds and fixes an electric wire connected to the wire connecting portion so that the electric wire elongates in a desired direction.
For example, an injector for ejecting fuel into a cylinder is attached to a cylinder head of a diesel engine. Electric wires which elongate from a control apparatus for controlling the operation of the injector are connected to a wire connecting portion disposed in a head portion of the injector. A portion of the wire connecting portion of the injector to which the electric wires are connected is covered with an insulating cover which is an insulating terminal cover, so that a leakage of electricity from the wire connecting portion is prevented from occurring.
All example of the structure of a portion in which such an insulating cover is attached to the injector will be described with reference to FIG. 8. A nut portion 2 is formed in a head portion of an injector 1. The nut portion 2 is a hexagonal tool engagement portion and with which a tightening tool such as a wrench is engaged when the injector 1 is screwed into an engine and fixed thereto. A disk-like flange 3 is formed below the nut portion 2. A connection piece 6 connected to an end portion of an electric wire 5 is attached by means of a nut 7 to each of a pair of terminals 4 which are protruded in the head portion of the injector 1 and function as wire connecting portions.
An insulating cover 300 which is to be fitted onto the head portion of the injector 1 has a body portion 8 having a substantially cylindrical shape, and a wire holding portion 9 which is continuously integrated with the body portion 8. When the body portion 8 is fitted onto the head portion of the injector 1, a plurality of engagement pawls 10 protruded from an inner periphery of the body portion 8 are engaged with the lower face of the flange 3. Therefore, the insulating cover 300 is held in an axial direction so as not to fall out of the head portion of the injector 1. The electric wires 5 which are connected to the terminals 4 of the injector 1 are held by the wire holding portion 9 of the insulating cover 300, so as not to come into contact with the engine body.
The above-described conventional insulating cover 300 is fitted onto the disk-like flange 3 disposed in the head portion of the injector 1, and the engagement pawls 10 are engaged with the lower face of the flange 3. In this construction, the insulating cover 300 can freely rotate about the axis of the injector 1 as indicated by arrows in FIG. 9.
The conventional insulating cover 300 has no problem in covering the head portion of the injector 1 for insulation. However, the insulating cover 300 involves a drawback in a function of holding the electric wires 5 so as to elongate in a desired direction. Specifically, if the other end portion of one of the electric wires 5 is pulled as a result of the leading conditions of the electric wire 5, the insulating cover 300 rotates, so that the insulating cover 300 cannot hold the electric wire 5 in a desired direction. As a result, the electric wire 5 comes in contact with other portions such as the engine, thereby producing a possibility that the insulating cover may be dropped off by vibration or the like, or the electric wire sheath may be broken.